Royal Dutch/Shell Group, Europe's second-largest oil company, will build its first liquefied natural gas plant in Qatar at a cost of about $6 billion to help meet surging global demand for the fuel, a Qatari official said on Sunday.

State-run Qatar Liquefied Natural Gas was to sign an accord with Shell for the plant, which will chill natural gas for export in tankers, said Faisal al-Suwaidi, the chairman of the company said in an interview in the capital, Doha.

The project will push the company ward its goal of becoming the world's top LNG producer with annual supply of 77 million tons by 2011 and fortify Shell's position as the product's top private supplier.

Companies are importing gas in tankers from Africa and the Middle East as supply falls from the North Sea and elsewhere.

For Shell, "gaining access to Qatar's LNG is critical for their long-term business," said Frank Harris, vice president of global LNG at Wood Mackenzie Ltd. in Edinburgh, an energy consultancy that advises oil companies. Shell officials in Doha declined to comment on the project ahead of the signing.

Shell beat ConocoPhillips and three others for the contract in Qatar, where Exxon Mobil leads foreign investors in tapping the nation's gas reserves, the world's third-largest.

"Exxon still appears to be the favored son in Qatar, but they are giving others a seat at the table," Harris said.

The new LNG plant will produce enough gas, 7.8 million tons a year, to power almost 8 million homes.

Some of the gas may be destined for Italy. In 2003, U.S. Energy Secretary Spencer Abraham and Federal Reserve Chairman Alan Greenspan called for an increase in LNG imports to help offset declining North American gas production.

Qatar is building the world's biggest LNG plants and ships as it seeks to overtake Indonesia to become the top exporter of the fuel. The Persian Gulf state's LNG output will almost quadruple to 77 million tons a year by 2012 from the current 20 million tons a year, Qatari officials have said.

Shell sold just over 11 million tons of LNG worldwide last year, making it the largest producer of liquefied natural gas. BP sold 8.7 million tons, and Exxon 5.7 million tons.

Shell in projects that account for 33 percent of 148 million tons a year of the gas that is chilled and compressed for shipment by tankers.

Qatar's offshore Persian Gulf North Dome field, the world's largest natural gas reservoir, is known to hold 900 trillion cubic feet of gas, of which about 130 trillion cubic feet is already earmarked for use in LNG projects, according to Wood Mackenzie.

It takes one trillion cubic feet of gas to produce 1 million tons of LNG annually, according to the consultant.

Qatar and Shell also are to sign a $3 billion petrochemical deal on Monday, Qatar's oil minister told Reuters on Sunday.

Abdullah al-Attiyah did not give further details of the deal, which will follow the liquefied natural gas agreement signed.Shell officials declined to comment.